If one or more of my players decide to go on a shopping spree, I've previously had problems describing the shop's inventory, without going into much detail or making it seem like the shop has only 2 items.
Of course, I can describe the atmosphere and the general nature of the inventory (e.g. "herbs" or "jewelry"), and that's just fine if the players walk into the shop looking for something specific, such as an herb that stops bleeding or a silver necklace with a sapphire embedded into it.
However, I'm unsure how to handle players that recently noticed "Hey, I've got 500 gold floating around that I want to spend on useless stuff". Or, in other words, players that want to look around for random shops with a random inventory to see if they find something of interest.
In the real world, this works, because you can literally walk into a random shop and look around to see if there's anything interesting. In D&D, the DM has to come up with something, and it's boring and frustrating for the players if it's always the same things.
So, what can I do to make random shopping interesting for the players, without for example preparing huge inventory lists in advance?